Microbial electrosynthesis (MES) for CO conversion
The microbial electrosynthesis (MES) is a platform to supply protons and electrons to improve the conversion efficiency and production rate for the valorization of C1 gas feedstock such as CO and CO2. The CO electrosynthesis achieved almost double of coulombic efficiency than the conventional CO2 electrosynthesis. The maximum volumetric acetate production rate was 0.71 g/L/day in the BES, which was 2–6 times higher than reported elsewhere. The efficient proton migration and electron transfer can enhance the productivity and conversion efficiency of the biological CO conversion in MES.
Microbial electrosynthesis for CO2 negative green H2 production
Conventional photoheterotrophic H2 production by purple sulfur bacteria requires additional organic substrates as the carbon and energy sources. We are investigating a novel photoautotrophic H2 production with concomitant CO2 uptake in MES. This enables to develop a CO2 negative green hydrogen production using electrode-driven process.
Metabolic flux analysis of bioconversion in BES
MES-driven bioconversin can be applied to polyhydroxybutrate (PHB) and methane production from CO2. The electrode associated biofilm contains PHB within the cell under different MES condition. The PHB is bio-derived and biodegradable plastic.
The anaerobic digestion effluent contains 40-50% of CO2 as well as CH4. Thus the additional process is needed to purify and refine the off gas. The MES-driven process prove reducing power to convert CO2 into CH4, called electromethanogenesis. The MES can convert synthetic and actual AD off gas (from 60 to 100 % of CO2) to over 99% of CH4.